We intend to implement and test the effectiveness of a comprehensive intervention to prevent functional disability among nursing home residents. The intervention acts by promoting exercise adoption and adherence and reversing institutional factors that cause resident inactivity. Our program, HEAL ('Helping Elders Activate their Lives'), represents an integration of two interventions developed independently from different theoretical models within our institute. A selected exercise component, based on progressive resistance training, promotes behavioral change among nursing home residents, and has been shown to be safe and efficacious in building muscle mass, improving performance-based tests of physical functioning, improving and preventing decline in activities of daily living. The universal nursing-based rehabilitation component targets social and environmental factors contributing to the problem of resident inactivity. We have shown that residents can be helped to be more self-involved in performance of daily activities by targeting behavior of nursing staff and social forces within the facility through training and encouraging a redirection of care planning towards each resident's functional capacity. Each of these interventions has been shown to be efficacious in preventing functional disability when implemented independently. Combined as the HEAL intervention model, the program facilitates the continuity of functional capacity gains resulting from the exercise program into the daily activity of nursing home residents. Making use of existing staffing at three triplets of matched facilities, the intervention will be implemented within the confines of a quasi-experimental trial, involving an estimated 1,350 residents from both randomly assigned experimental exercise only, experimental exercise and nursing based rehabilitation, and usual care control homes. Performance on functional status, and physiologic, mood and self-efficacy measures will be collected at baseline and months 4, 8, 12 and 16 of the intervention. The aim of the proposed study is to establish the effectiveness of this intervention acting in a real world setting. Specifically, we hypothesize that the intervention will act proximally in 1) promoting resident exercise behavior, 2) improve performance on physiologic tests, and 3) act distally to prevent further functional decline and facilitate functional improvement. Further, we anticipate significant carry over effects on mood, well-being, self-efficacy and quality of life outcomes.